Rett Syndrome
Early Signs of Rett Syndrome at 12–18 Months
Between 12 and 18 months, early signs of Rett Syndrome often include a slowing or loss of skills a child once had — especially purposeful hand use, replaced by repetitive hand wringing or mouthing — alongside slowing head growth, movement changes and loss of emerging words. Because this involves regression and a genetic change, it warrants prompt medical review, not home diagnosis.
Your daughter was reaching her milestones, and now something feels different — here's how to understand what you're noticing, gently and clearly.
In short
Rett Syndrome (ICD-11 LD90.0) often shows a distinctive pattern in the second year: a baby who was developing as expected begins to slow down or lose skills she had already gained — particularly purposeful hand use and emerging words. The hallmark sign is a loss of meaningful hand skills replaced by repetitive hand movements such as wringing, mouthing or hand-to-hand rubbing, alongside slowing head growth. These are signs to observe and discuss promptly with a clinician — never to diagnose at home.Early signs to watch between 12 and 18 months
A pause or regression after early typical development- Skills that were emerging — babbling, words, reaching, grasping — begin to fade or plateau
- A period of withdrawal or reduced eye contact and social interest, which can later partly recover
Loss of purposeful hand use
- Stops using hands to reach, hold or explore toys the way she used to
- Repetitive hand movements appear — wringing, squeezing, clapping, tapping, mouthing or washing-like motions, often near the midline
Movement and growth changes
- Slowing of head growth (the head circumference your paediatrician tracks may fall away from its earlier curve)
- Unsteady, wide-based or stiff walking, or delay in walking; reduced muscle tone or unusual stiffness
Communication and breathing
- Loss of emerging spoken words or reduced communicative sounds
- In some children, irregular breathing patterns while awake (breath-holding or fast breathing) — though these often become clearer a little later
What distinguishes this from ordinary variation is the loss or regression of skills a child once had, especially purposeful hand use, rather than a simple delay in gaining new ones.
When to seek a check
Because Rett Syndrome involves a genetic change and can affect movement, growth and breathing, any regression — losing skills your child previously had — warrants a prompt medical review with your paediatrician, who may arrange genetic testing (commonly MECP2) and onward specialist assessment. This is a medical-referral situation first; therapies such as occupational, physiotherapy and communication support then play a vital role in nurturing comfort, connection and ability.The Pinnacle way
At [Pinnacle Blooms Network](/), we walk beside families with warmth and a strengths-first lens — focusing on what your daughter can do and how we grow it. Targeted support like occupational therapy helps protect hand function, movement and daily participation, while you learn more about Rett Syndrome and what to expect. A clinical AbilityScore® and any diagnosis are formed only at a Pinnacle Blooms Network centre under qualified clinician care; nothing here is a diagnosis. Across 70+ centres in 4 states and 4.95 lakh+ families served, our aim is steady, compassionate progress.Trusted sources
Aligned with WHO ICD-11 (LD90.0 Rett syndrome), and developmental and child-health guidance from the American Academy of Pediatrics and HealthyChildren.org on monitoring milestones and acting early when skills are lost.Next step — if you've noticed your daughter losing skills or changing how she uses her hands, please speak with your paediatrician now, and book a developmental screen with our clinical team on WhatsApp at +91 91001 81181 — let's understand this together.
This is general information, not a diagnosis — a clinical AbilityScore® and any diagnosis are formed only at a Pinnacle Blooms Network centre under qualified clinician care.
What to watch
Watch for regression — losing skills she once had, especially purposeful hand use replaced by repetitive wringing or mouthing — plus slowing head growth, unsteady walking and loss of emerging words. Any loss of skills warrants a prompt paediatric review.
Try this at home
Keep a simple dated note or short video of what your daughter can do with her hands and her sounds. A clear before-and-after record helps your paediatrician see change quickly and act early.
Trusted sources
Developed by SETU Consortium · Pinnacle Blooms Network · Last reviewed 2026-06-10
This is general information, not a diagnosis. A clinical AbilityScore® and any diagnosis are formed only at a Pinnacle Blooms Network centre, under qualified clinician care.
Frequently asked
Is losing skills the same as a developmental delay?
Not quite. A delay means a child is slower to gain new skills, while regression means losing skills she already had. Rett Syndrome characteristically involves regression — particularly losing purposeful hand use — which is why any loss of skills should be reviewed promptly by your paediatrician.
Does Rett Syndrome only affect girls?
It is far more common in girls because of how the genetic change (most often in the MECP2 gene) affects development, though it can rarely occur in boys. Diagnosis is confirmed by a clinician through assessment and genetic testing, not by signs alone.
What should I do first if I notice these signs?
Speak with your paediatrician promptly, as this is a medical-referral situation. They may arrange genetic testing and specialist assessment. Therapies such as occupational therapy then support hand function, movement and daily participation.